Somerset · England
Floor joist repairs in Somerset
Across Somerset, requests for floor joist repairs usually begin with a crack someone has noticed getting wider. Clay soils are found in parts of Somerset. A repair only lasts if the reason for the movement has stopped.
Guide price from£260per joist inc VAT

- Area
- Somerset
- Pricing region
- South West
- Ground
- Clay in parts
- Towns listed
- 11
Is Somerset prone to ground movement?
Somerset mixes Lias clays, Mercia Mudstone, limestone hills and the peat and alluvium of the Levels around Bridgwater, which can settle. The former Somerset coalfield around Radstock and Midsomer Norton left recorded workings.
Parts of Somerset lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Housing stock in Somerset: Bath stone Georgian terraces, Victorian houses in Taunton and Weston-super-Mare, and post-war estates.
What to expect when we carry out floor joist repairs
Photos and a call
Send photos of the dip or soft area, the outside wall at ground level and any air bricks. A short call about when it started, and any recent plumbing or heating work, tells us whether the problem is local or widespread.
Written quote
You get a no-obligation written quote listing which joists are sistered, spliced or replaced and any sleeper wall or ventilation work. It becomes a fixed price in writing once the repair is specified.
Repair the structure
Boards are lifted and numbered if they are going back, and rotten timber is cut out. New treated timber is fixed and checked with a level before strutting, hangers and any restraint straps go in.
Is it time for floor joist repairs? Common signs
- Floor bouncing, or ornaments rattling, when someone walks across
- Soft or spongy boards near outside walls, hearths or the bathroom
- A musty smell, or fungal strands showing between the boards
- Floor dipping towards an outside wall or in the middle of the room
What should you budget for floor joist repairs in Somerset?
Prices in Somerset are worked out on South West rates. They include VAT and are a starting point: access, the extent of the damage and whether an engineer or building control is involved all move the figure.
| Item | Guide price | Per |
|---|---|---|
| Splicing or sistering a damaged joist | £260 – £410 | per joist |
| Whole room of joists and boards | £2,050 – £6,200 | per room |
| Sleeper wall rebuild and ventilationest. | £410 – £1,550 | per room |
Repair options we may recommend
Replacing joists and boards
When rot or woodworm runs through most of a floor, it is usually cheaper to replace the joists, strutting and boards together. Where joists run parallel to an outside wall, restraint straps tie the new floor back to it so the wall keeps its lateral support.
Best for: Widespread rot, or a whole floor that has dropped
Splicing ends and fitting hangers
Where only the end has rotted, it is cut back to sound timber and a new piece is fixed alongside, bearing on the wall or on a new joist hanger. Missing or under-nailed hangers elsewhere are replaced at the same time. The damp in the wall must be fixed too.
Best for: Rotten joist ends in damp solid walls
Sistering a joist
A new length of treated timber, the same depth as the original, is bolted or screwed alongside the damaged joist so the two share the load. It is the quickest fix for a notched, cracked or sagging joist that is otherwise sound, usually after lifting a few boards.
Best for: Cut, cracked or sagging joists with sound ends
Do you need approval for floor joist repairs in England?
Like-for-like repairs such as crack stitching and repointing do not usually need building control approval in England, but anything that changes or strengthens the structure, such as underpinning or rebuilding a wall, does. If the work touches a party wall, the Party Wall etc. Act 1996 may apply.
Floor joist repairs near you in Somerset
Your floor joist repairs questions
Does the ground around Bath cause cracking?
Somerset mixes Lias clays, Mercia Mudstone, limestone hills and the peat and alluvium of the Levels around Bridgwater, which can settle. The former Somerset coalfield around Radstock and Midsomer Norton left recorded workings. Parts of Somerset lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Only an investigation on site can say why a particular building has moved.
How much will floor joist repairs cost in Somerset?
On South West rates, floor joist repairs starts from about £260 per joist, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
Why is my floor bouncy?
A bouncy floor usually means the joists are deflecting too much, often because they span too far, have lost their strutting or have been weakened by notches. It rarely means imminent failure, but it is worth checking, especially if the bounce appeared after work in the room.
Is a sagging floor dangerous?
A gentle, long-standing sag is usually not dangerous, and many older floors have moved slightly over a century. A sag that is getting worse, soft boards or a floor dropping near a wall needs checking soon, because rotten joist ends can lose their bearing.
Can floor joists be repaired without taking up the whole floor?
Yes, in most cases only the boards over the affected joists need lifting, and three or four boards are often enough to sister a joist or splice a rotten end. Widespread rot is the exception, because the whole floor must come up to remove the decay.